Sage Pay Form Version: 1.2

About a week ago, for some bizarre strange reason we started getting duplicate payments from clients on our oscommerce shop using Sage Pay Form Version: 1.2 The problem is no matter what the client do and we have tested it you always get redirected from sagepay to /checkout_payment.php?payment_error=sage_pay_form with the default message

There has been an error processing your order transaction
Please try again and if problems persist, please try another payment method.

The the client try again and sometimes with a different card and the same thing happen again.

In live.sagepay the transaction is successfull but on the oscommerce it seem to fail all the time.

I believe it got something to do with the sucess url / failure url but not sure where the problem is. I have deleted and re uploaded the sape pay form 1.2 files again but the same problem. When I spoke to sagepay they say the problem is with the oscommerce shop and dont support it....

Any advice would be appreciated..... having to do a number of refunds and have a few unhappy clients

Read the other posts on form problems. No developers seem to read this forum or provide answers and I certainly wasted much time on form. change to "server" method.

I'm feeling lucky today......maybe someone will answer my post!
I do try and answer a simple post when I can just to give something back.
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